IO.SYS & MSDOS.SYS File Sizes Don't Change After Uninstalling

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Article ID: 100853 - View products that this article applies to.
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If you remove MS-DOS 6 Upgrade using the Uninstall disk you created during installation, IO.SYS and MSDOS.SYS still have the MS-DOS 6 file sizes (the original date and time are correct).


This situation occurs because Uninstall overwrites the MS-DOS 6 IO.SYS and MSDOS.SYS files with the previous versions of IO.SYS and MSDOS.SYS but does not delete the MS-DOS 6 files first (nor does it truncate the files after overwriting them).


Although this problem occurs with other versions of MS-DOS, the following table only shows the files sizes before and after installation and uninstall with MS-DOS 5.0 and MS-DOS 6.0.
                                                MS-DOS 5 after
   File           MS-DOS 5        MS-DOS 6     Unstalling MS-DOS 6

   IO.SYS           33430          40470              40470
   MSDOS.SYS        37394          38138              38138


Article ID: 100853 - Last Review: October 22, 2013 - Revision: 1.0
  • Microsoft MS-DOS 6.0 Standard Edition
kbnosurvey kbarchive KB100853

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